Recently, interest has grown in the possible role that men who have sex with men and women (MSMW) may play as a "bridge", spreading infection acquired through their same sex contacts to their female partners. The subpopulation of MSMW who may be most likely to place their female partners at risk are ones who hide their same sex behavior from these women, are not gay identified, and are sexually active with both men and women. These men have not been the focus of previous research. Consequently, we know very little about: the sexual behaviors these men engage with male and female partners, including to what extent they place themselves at risk of infection;whether they adopt risk-reduction strategies to avoid acquiring or transmitting infection;their reasons and strategies for concealing their same sex;if they feel vulnerable to acquiring HIV infection;and whether they perceive a need for HIV testing, education or prevention interventions. To address these gaps and examine race/ethnic differences in sexual behavior, we propose an investigation of 200 MSMW - 60 African Americans, 60 Latinos, 60 non-Hispanic Whites. Within each of these racial/ethnic groups, 20 cases will have previously tested HIV-positive. We will also include 20 MSMW who are Asian, Pacific Islanders, American Indians, or Alaskan Natives. Eligible men must be non gay- identified and in the past year: had anal or oral sex with a man;had vaginal, anal or oral sex with a woman to whom they had been in a relationship for at least 3 months;and concealed their same sex behavior from all their female partners. The study's specific aims are: 1. To identify what psychological, social, and sexual needs fulfilled by MSMW's relationships with men and with women;2. To investigate MSMW's reasons and motives for concealing their same sex behavior from their female partners, and the social and psychological costs associated with this concealment;3. To identify the various impression management strategies, both active and passive, that MSMW use to maintain their desired social identity (e.g., as a heterosexual man) with their male and female partners;4. To investigate the potential differences in the sexual behaviors and risk reduction strategies MSMW engage in with their male and female partners;5. To examine how MSMW's understandings of their sexual behavior with men and women in different venues and, how these contexts and activities that take place within them facilitate cognitive escape. The study's finding will offer novel and important information about a high risk subpopulation of MSMW, and will yield important information that can guide the development of preventive interventions.